Hi. I just got a Drake Ceramic tenor mpc. I really like it! It's used, with a little chipping just on the inside of the tip, (very small). Two questions: 1) Should I repair the small chipped surface...would it make a difference" As I said, they are quite small and the piece blows good for me. 2) How can I tell what model it is? The only figures on it look like a serial no. Thanks for any input.